Single-frequency tunable 4473 nm laser by frequency doubling of tapered amplified diode laser at cesium D1 line

A continuous single-frequency tunable blue laser at 447.3 nm is developed by external-cavity frequency doubling of a tapered amplifier-boosted continuous-wave diode laser at cesium (Cs) D₁ line. A maximum blue power of 178 mW with 50.8% conversion efficiency is obtained. It can be continuously tuned over a range around 1.6 GHz as the diode laser frequency is scanned across the $F=4\to F^{\prime }=3$ transition of ¹³³Cs D₁ line. The generated tunable and stable blue laser source has potential applications in constructing quantum light-atom interfaces in quantum networks.